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Topic Review
Lake Taupo
Lake Taupo, often spelled Taupō, is a lake in the North Island of New Zealand. It is in the caldera of the Taupo Volcano. The lake is the namesake of the town of Taupō, which sits on a bay in the lake's north-eastern shore. With a surface area of 616 square kilometres (238 sq mi), it is the largest lake by surface area in New Zealand, and the second largest freshwater lake by surface area in geopolitical Oceania after Lake Murray in Papua New Guinea. Motutaiko Island lies in the south east area of the lake. Lake Taupo has a perimeter of approximately 193 kilometres and a maximum depth of 186 metres. It is drained by the Waikato River (New Zealand's longest river), and its main tributaries are the Waitahanui River, the Tongariro River, and the Tauranga Taupo River. It is a noted trout fishery with stocks of introduced brown and rainbow trout. The level of the lake is controlled by Mercury Energy, the owner of the eight hydroelectric dams on the Waikato River downstream of Lake Taupo, using gates built in 1940–41. The gates are used to reduce flooding, conserve water and ensure a minimum flow of 50 m3/s (1,800 cu ft/s) in the Waikato River. The resource consent allows the level of the lake to be varied between 355.85 and 357.25 metres (1,167.5 and 1,172.1 ft) above sea level.
  • 1.3K
  • 08 Nov 2022
Topic Review
Hydrotalcite as CO2 Sinks for Climate Change Mitigation
Hydrotalcites are known in the bibliography as LDHs (Layered double hydroxides). Hydrotalcites, as such, are not good CO2 absorbents due to poor basic properties and presence of entities that hinder CO2 adsorption and are therefore subjected to thermal treatment (around 500 °C) to obtain nearly amorphous metastable mixed solid solutions known as calcined layered double hydroxides (CLDHs). There are several parameters that can make hydrotalcites suitable for use as CO2 sinks. 
  • 1.3K
  • 11 Jul 2022
Topic Review
Reinforcement (Speciation)
Reinforcement is a process of speciation where natural selection increases the reproductive isolation (further divided to pre-zygotic isolation and post-zygotic isolation) between two populations of species. This occurs as a result of selection acting against the production of hybrid individuals of low fitness. The idea was originally developed by Alfred Russel Wallace and is sometimes referred to as the Wallace effect. The modern concept of reinforcement originates from Theodosius Dobzhansky. He envisioned a species separated allopatrically, where during secondary contact the two populations mate, producing hybrids with lower fitness. Natural selection results from the hybrid's inability to produce viable offspring; thus members of one species who do not mate with members of the other have greater reproductive success. This favors the evolution of greater prezygotic isolation (differences in behavior or biology that inhibit formation of hybrid zygotes). Reinforcement is one of the few cases in which selection can favor an increase in prezygotic isolation, influencing the process of speciation directly. This aspect has been particularly appealing among evolutionary biologists. The support for reinforcement has fluctuated since its inception, and terminological confusion and differences in usage over history have led to multiple meanings and complications. Various objections have been raised by evolutionary biologists as to the plausibility of its occurrence. Since the 1990s, data from theory, experiments, and nature have overcome many of the past objections, rendering reinforcement widely accepted,:354 though its prevalence in nature remains unknown. Numerous models have been developed to understand its operation in nature, most relying on several facets: genetics, population structures, influences of selection, and mating behaviors. Empirical support for reinforcement exists, both in the laboratory and in nature. Documented examples are found in a wide range of organisms: both vertebrates and invertebrates, fungi, and plants. The secondary contact of originally separated incipient species (the initial stage of speciation) is increasing due to human activities such as the introduction of invasive species or the modification of natural habitats. This has implications for measures of biodiversity and may become more relevant in the future.
  • 1.3K
  • 28 Apr 2023
Topic Review
Solar Energy Systems into Seawater Desalination
Solar energy, amongst all renewable energies, has attracted inexhaustible attention all over the world as a supplier of sustainable energy. The energy requirement of major seawater desalination processes such as multistage flash (MSF), multi-effect distillation (MED) and reverse osmosis (RO) are fulfilled by burning fossil fuels, which impact the environment significantly due to the emission of greenhouse gases. The integration of solar energy systems into seawater desalination processes is an attractive and alternative solution to fossil fuels. 
  • 1.3K
  • 29 Sep 2022
Topic Review
Exposure Routes and Health Risks Associated with Pesticides
There are four main pesticide application methods, including hydraulic spraying, backpack spraying, basal trunk spraying, and aerial spraying. Pesticide application methods are mainly selected by considering the habits of target pests, the characteristics of target sites, and the properties of pesticides. Humans are directly exposed to pesticides in occupational, agricultural, and household activities and are indirectly exposed to pesticides via environmental media, including air, water, soil, and food. Human exposure to pesticides occurs mainly through dermal, oral, and respiratory routes. People who are directly and/or indirectly exposed to pesticides may contract acute toxicity effects and chronic diseases. Although no segment of the general population is completely protected against exposure to pesticides and their potentially serious health effects, a disproportionate burden is shouldered by people in developing countries. Both deterministic and probabilistic human health risk assessments have their advantages and disadvantages and both types of methods should be comprehensively implemented in research on exposure and human health risk assessment. Equipment for appropriate pesticide application is important for application efficiency to minimize the loss of spray solution as well as reduce pesticide residuals in the environment and adverse human health effects due to over-spraying and residues. Policymakers should implement various useful measures, such as integrated pest management (IPM) laws that prohibit the use of pesticides with high risks and the development of a national implementation plan (NIP) to reduce the adverse effects of pesticides on the environment and on human health. 
  • 1.3K
  • 30 Jul 2022
Topic Review
Energiewende in Germany
The Energiewende (German for energy transition) is the planned transition by Germany to a low carbon, environmentally sound, reliable, and affordable energy supply. The term Energiewende is regularly used in English language publications without being translated (a loanword).:4 The new system will rely heavily on renewable energy (particularly wind, photovoltaics, and hydroelectricity), energy efficiency, and energy demand management. Most if not all existing coal-fired generation will need to be retired. The phase-out of Germany's fleet of nuclear reactors, to be complete by 2022, is a key part of the program. Legislative support for the Energiewende was passed in late 2010 and includes greenhouse gas (GHG) reductions of 80–95% by 2050 (relative to 1990) and a renewable energy target of 60% by 2050. These targets are ambitious. The Berlin-based policy institute Agora Energiewende noted that "while the German approach is not unique worldwide, the speed and scope of the Energiewende are exceptional". The Energiewende also seeks a greater transparency in relation to national energy policy formation. Germany has made significant progress on its GHG emissions reduction target, achieving a 27% decrease between 1990 and 2014. However the country will need to maintain an average GHG emissions abatement rate of 3.5% per year to reach its Energiewende goal, equal to the maximum historical value thus far. As of 2013, Germany spends €1.5 billion per year on energy research in an effort to solve the technical and social issues raised by the transition. This includes a number of computer studies that have confirmed the feasibility and a similar cost (relative to business-as-usual and given that carbon is adequately priced) of the Energiewende.
  • 1.3K
  • 09 Oct 2022
Topic Review
Bioethanol Production of Distillery Stillage
Distillery stillage has a high energy potential (13.6 MJ/kg TS, 10.4 MJ/kg COD), which indicates that it can be processed via anaerobic digestion and is a suitable substrate for conversion into energy.
  • 1.3K
  • 16 Nov 2021
Topic Review
Food Packaging
Demand for food packaging is on the rise as a result of increasing global demand for food due to population growth. Most of the food packaging are used on-the-go and are single-use plastics that are disposed of within a short space of time. The bulk of this plastic waste has found its way into the environment contaminating land, water and the food chain. The food industry is encouraged to reduce, reuse and recycle packaging materials. 
  • 1.3K
  • 09 Apr 2021
Topic Review
Marine Bacterial Natural Products
Marine bacterial natural products are molecules produced by marine bacteria through secondary metabolism genes, which can provide them with competitive advantages. Certain natural products can have bioactive effects (e.g. antimicrobial properties) and thus can be used by humans as therapeutics or leads for novel therapeutics.
  • 1.3K
  • 15 Oct 2020
Topic Review
Effects of Environmental Changes in the Amazon Region
Environmental changes caused by human activities alter the water, energy, and carbon cycles in the Amazon region. This has resulted in biological changes across several plant species, some of which are used in both regional and global trade and represent important sources of food and income for people. Reports from local people and scientific studies point to the effects of deforestation, forest degradation, and climate change on native plant species. Indeed, people who are typically dependent on natural resources and ecosystem services are the most threatened by plant species productivity and geographical distribution changes. However, there is a lack of scientific literature concerning the effects of environmental changes on plant species and forest-dependent communities in the Amazon region.
  • 1.3K
  • 28 Mar 2022
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